(*  Title:      Pure/ML-Systems/mlworks.ML

    ID:         $Id$

    Author:     Lawrence C Paulson, Cambridge University Computer Laboratory

    Copyright   1996  University of Cambridge

Compatibility file for MLWorks version 1.0r2 or later.

*)

(** ML system related **)

(* restore old-style character / string functions *)

fun ord s = Char.ord (String.sub (s, 0));

val chr = str o Char.chr;

val explode = (map str) o String.explode;

val implode = String.concat;

(* MLWorks parameters *)

val _ =

 (MLWorks.Internal.Runtime.Event.stack_overflow_handler

    (fn () => MLWorks.Internal.Runtime.Memory.max_stack_blocks :=

      ! MLWorks.Internal.Runtime.Memory.max_stack_blocks + 20);

  MLWorks.Internal.Runtime.Memory.gc_message_level := 10;

  (*Is this of any use at all?*)

  Shell.Options.set (Shell.Options.ValuePrinter.showExnDetails, true));

(* Poly/ML emulation *)

(*To exit the system with an exit code -- an alternative to ^D *)

fun exit 0 = (OS.Process.exit OS.Process.success): unit

  | exit _ = OS.Process.exit OS.Process.failure;

fun quit () = exit 0;

(*limit the printing depth*)

fun print_depth n = Shell.Options.set (Shell.Options.ValuePrinter.maximumDepth, n);

(*interface for toplevel pretty printers, see also Pure/install_pp.ML*)

(*n.a.*)

fun make_pp path pprint = ();

fun install_pp _ = ();

(*prompts*)

(*n.a.??*)

fun ml_prompts p1 p2 = ();

(** Compiler-independent timing functions **)

(*Note start point for timing*)

fun startTiming() = 

  let val CPUtimer = Timer.startCPUTimer();

      val time = Timer.checkCPUTimer(CPUtimer)

  in  (CPUtimer,time)  end;

(*Finish timing and return string*)

fun endTiming (CPUtimer, {gc,sys,usr}) =

  let open Time  (*...for Time.toString, Time.+ and Time.- *)

      val {gc=gc2,sys=sys2,usr=usr2} = Timer.checkCPUTimer(CPUtimer)

  in  "User " ^ toString (usr2-usr) ^

      "  GC " ^ toString (gc2-gc) ^

      "  All "^ toString (sys2-sys + usr2-usr + gc2-gc) ^

      " secs"

      handle Time => ""

  end;

(* ML command execution *)

(*Can one redirect 'use' directly to an instream?*)

fun use_text _ txt =

  let

    val tmp_name = OS.FileSys.tmpName ();

    val tmp_file = TextIO.openOut tmp_name;

  in

    TextIO.output (tmp_file, txt);

    TextIO.closeOut tmp_file;

    use tmp_name;

    OS.FileSys.remove tmp_name

  end;

(** OS related **)

(* system command execution *)

(*execute Unix command which doesn't take any input from stdin and

  sends its output to stdout; could be done more easily by Unix.execute,

  but that function doesn't use the PATH*)

fun execute command =

  let

    val tmp_name = OS.FileSys.tmpName ();

    val is = (OS.Process.system (command ^ " > " ^ tmp_name); TextIO.openIn tmp_name);

    val result = TextIO.inputAll is;

  in

    TextIO.closeIn is;

    OS.FileSys.remove tmp_name;

    result

  end;

(* file handling *)

(*get time of last modification; if file doesn't exist return an empty string*)

fun file_info "" = ""		(* FIXME !? *)

  | file_info name = Time.toString (OS.FileSys.modTime name) handle _ => "";

(* getenv *)

fun getenv var =

  (case OS.Process.getEnv var of

    NONE => ""

  | SOME txt => txt);

(* non-ASCII input (see also Thy/use.ML) *)

val needs_filtered_use = false;